WATCH: Wozniacki won on her return to action in Montréal, defeating Kimberly Birrell in straight sets.

NEW YORK—The Caroline Wozniacki comeback is off and running at the 2023 US Open as the former world No. 1 scores her biggest win since returning from retirement, shocking No. 11 seed Petra Kvitova, 7-5, 7-6 (5).

Rivals since both began their rise up the rankings in the late 2000s, Wozniacki won their first meeting since they faced off at the 2018 WTA Finals to put herself a win away from the second week—edging over the finish line in straight sets under the Arthur Ashe Stadium lights.

"I've been feeling very comfortable here in New York in general," she said after the match. "Ever since I arrived here, it's just something about the courts, everything else, that have made me feel good.

"I feel like I played well today. I'm so happy I managed to close it out, even missing a couple of those match points. I'm happy that I just stayed calm and collected and I managed to win in the end anyways."

Wozniacki has been one of the stories of the summer since announcing her intent to end a three-year retirement, during which she gave birth to two children, and resume her professional career at the Omnium Banque Nationale in Montréal. Winning just one match out of three in Montréal and Cincinnati, expectations may have been lower heading into her first Grand Slam appearance since the 2020 Australian Open, but the two-time US Open finalist has been in vintage form since returning to the USTA Billie Jean King National Tennis Center.

"It feels amazing to beat such an amazing player and champion like Petra," she said. "Obviously I knew coming into the match that I had a chance to win, and I believe in myself. At the same time she obviously has had a great year. She's No. 11 in the world, loves to play on hard courts. I knew it was going to be a very tough one and I had to play my best tennis. I'm just so thrilled to have an opportunity to play out on Arthur Ashe Stadium. What an honor that is, play a night session in front of this amazing crowd.

"I said it on court, but three years ago if you'd asked me, I didn't think I was ever going to play on one of those courts again in the US Open, especially a night session. It just feels pretty incredible to be out there and winning a match like that."


Three years ago if you'd asked me, I didn't think I was ever going to play on one of those courts again in the US Open, especially a night session. It just feels pretty incredible to be out there and winning a match like that. Caroline Wozniacki

Dazzling the New York crowd in a bright-blue bodysuit, she scored a straight-set win over qualifier Tatiana Prozorova to renew her rivalry with Kvitova, whom she played 14 times—often at critical points in either or both of their careers, whether it was in at the 2010 Wimbledon Championships when Kvitova beat Wozniacki en route to her first Grand Slam semifinal, or later that year in Beijing when Wozniacki avenged the loss and clinched her first week atop the WTA rankings.

Kvitova, who soldiered on through Wozniacki’s extended maternity leave, has enjoyed flashes of brilliance in 2023, most notably at the Miami Open where she won her first WTA 1000 title since the 2018 Mutua Madrid Open, and has been ranked inside the Top 10 for most of the season. Down to No. 11 before the US Open, Kvitova’s inimitable offense nonetheless had Wozniacki on the backfoot early in the match, helping her secure an early-break advantage.

Wozniacki proved more consistent from there, winning five of the next six games to sweep the opening set; the Dane soon found herself two games from victory with a 4-2 lead in the second.

Though Kvitova pulled off a comeback of her own—saving two match points to force a tiebreaker—the Czech faded in the Sudden Death, throwing in an ill-timed double fault to hand Wozniacki the early initiative and help her lead 4-2 at the first change of ends.

Earning two more match points, Wozniacki converted her fourth to earn her first Top 20 win since beating Kvitova in Singapore at the 2018 Finals.

Awaiting her in the next round is fellow comeback kid Jennifer Brady, who is also playing her first major tournament since 2021 Roland Garros. The American has spent much of the last two years dealing with a knee injury, but is displaying some of the form that took her to the 2021 Australian Open final in Flushing, defeating 2023 semifinalist Magda Linette in three sets on Louis Armstrong Stadium earlier Wednesday evening.